Widmer A F, Wiestner A, Frei R, Zimmerli W
Department of Internal Medicine, University Hospital, Basel, Switzerland.
Antimicrob Agents Chemother. 1991 Apr;35(4):741-6. doi: 10.1128/AAC.35.4.741.
Antimicrobial therapy of device-related infections often fails, despite the in vitro susceptibility of the infecting strain. Therefore, alternative laboratory-based in vitro tests are required to predict the outcome. Fleroxacin, ciprofloxacin, aztreonam, and co-trimoxazole were tested against Escherichia coli ATCC 25922 in vitro and in the tissue-cage animal model. The importance of early treatment was evaluated by starting the drugs either 30 min before or 4, 12, and 24 h after bacterial challenge. Results were compared with the in vitro drug efficacy against nongrowing and adherent Escherichia coli ATCC 25922. The alternative in vitro tests correlated highly with the outcome in the tissue-cage animal model. In the prophylaxis group (drug given 30 min before bacterial challenge), co-trimoxazole was less efficacious than the other three drugs (P less than 0.001). In delayed treatment, ciprofloxacin showed the highest cure rate. It was also more potent than the other drugs against nongrowing and adherent E. coli ATCC 25922. The efficacies of aztreonan, fleroxacin, and ciprofloxacin dropped significantly (P less than 0.01) when the time interval between bacterial challenge and the start of treatment was delayed to greater than 4 h. These data emphasize (i) the need for proper timing of prophylaxis in patients undergoing implant surgery, and (ii) the possibility of successful treatment of established device-related infections with drugs which kill not only growing but also nongrowing and adherent bacteria.
尽管感染菌株在体外药敏试验中显示敏感，但与装置相关感染的抗菌治疗常常失败。因此，需要基于实验室的其他体外试验来预测治疗结果。对氟罗沙星、环丙沙星、氨曲南和复方新诺明进行了体外试验以及在组织笼动物模型中对大肠杆菌ATCC 25922进行了试验。通过在细菌攻击前30分钟或攻击后4、12和24小时开始用药来评估早期治疗的重要性。将结果与这些药物对非生长和黏附的大肠杆菌ATCC 25922的体外药效进行比较。其他体外试验与组织笼动物模型中的结果高度相关。在预防组（细菌攻击前30分钟给药）中，复方新诺明的疗效低于其他三种药物（P小于0.001）。在延迟治疗中，环丙沙星显示出最高的治愈率。它对非生长和黏附的大肠杆菌ATCC 25922也比其他药物更有效。当细菌攻击与开始治疗之间的时间间隔延迟至大于4小时时，氨曲南、氟罗沙星和环丙沙星的疗效显著下降（P小于0.01）。这些数据强调了（i）接受植入手术患者进行适当预防时机的必要性，以及（ii）使用不仅能杀死生长细菌而且能杀死非生长和黏附细菌的药物成功治疗已确立的装置相关感染的可能性。
